/* Problem URL: https://codeforces.com/contest/2117/problem/D */ #include using namespace std; #define V vector #define rmin(a, b) a = min(a, b) #define rmax(a, b) a = max(a, b) #define rep(i, lim) for (int i = 0; i < (lim); i++) #define nrep(i, s, lim) for (int i = s; i < (lim); i++) #define repv(i, v) for (auto &i : (v)) #define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; } #define sortv(v) sort(v.begin(), v.end()) #define all(v) (v).begin(), (v).end() using vi = vector; using vvi = vector; using vvvi = vector; using vvvvi = vector; using ll = long long; using vl = vector; using vvl = vector; using vvvl = vector; using vvvvl = vector; template auto operator<<(ostream &os, const vector &vec)->ostream& { os << vec[0]; for (size_t i = 1; i < vec.size(); i++) { os << ' ' << vec[i]; } os << '\n'; return os; } template auto operator>>(istream &is, vector &vec)->istream& { for (auto &i : vec) { is >> i; } return is; } template auto operator<<(ostream &os, const vector> &vec)->ostream& { for (auto &i : vec) { os << i[0]; for (size_t j = 1; j < i.size(); j++) { os << ' ' << i[j]; } os << '\n'; } return os; } template auto operator>>(istream &is, vector> &vec)->istream& { for (auto &i : vec) { for (auto &j : i) { is >> j; } } return is; } int main() { ios::sync_with_stdio(false); cin.tie(nullptr); int t; cin >> t; while (t--) { ll n; cin >> n; vl fds(n); cin >> fds; bool dec = true; bool cres = true; nrep(i, 1, n) { if (fds[i] > fds[i - 1]) { dec = false; } if (fds[i] < fds[i - 1]) { cres = false; } } if (!dec && !cres) { cout << "NO\n"; continue; } if (dec) { reverse(all(fds)); } ll ans = fds.back() - n * fds[0]; bool pos = true; if (ans % (-n * n + 1) || ans > 0) { cout << "NO\n"; continue; } ans /= -n * n + 1; rep(i, n) { fds[i] -= ans * (n - i); } ll tmp = fds[0]; nrep(i, 1, n) { if (fds[i] - tmp * (i + 1) != 0) { pos = false; break; } } cout << (pos ? "YES\n" : "NO\n"); } }